All pronunciations in the Oxford Advanced American Dictionary are American pronunciations.
In the written pronunciations, the following symbols are used:
If more than one written pronunciation is given for a word, they are all acceptable, but the first form given is the most common. Not all possible American pronunciations are shown in this dictionary. For example, some speakers only use the sound /ɔ/ when it is follwed by /r/ (as in horse /hɔrs/) and use /ɑ/ in all other words that are shown with /ɔ/ in this dictionary, so that they pronounce both caught and cot as /kɑt/.
/ ˈ / shows the strong stress in a word or group of words. It is in front of the part (or syllable) that you say most strongly. For example, any /ˈɛni/ has a stress on the first syllable; depend /dɪˈpɛnd/ has a stress on the second syllable.
/ ˌ / shows a weaker (or secondary) stress. Many longer words have a syllable that is pronounced with a secondary stress as well as a syllable with strong (or main) stress. So in the word pronunciation /prəˌnʌnsiˈeɪʃn/, the main stress is on the syllable /ˈeɪ/, and the secondary stress is on the syllable /ˌnʌn/.
American speakers use the sound / t̮ /, which is like a quick /d/, in many words spelled with -t- or -tt-. It is used in words after a vowel or /r/, and before an unstressed vowel or syllablic /l/: city /ˈsɪt̮ɪ /; parting /ˈpɑrt̮ɪŋ /; little /ˈlɪt̮l /.
Some very common words, for example an, for, of, and that, have two or more pronunciations: a strong form and one or more weak forms. For example, for is pronounced /fər/ in the sentence It’s for you. The strong form occurs when the word comes at the end of a sentence or when it is given special emphasis. For example, for is pronounced / fɔr/ in Who’s it for? and The present isn’t from Anna, it’s for her.